Augmenting and facilitating flushing in magnetic separation

Abstract

Apparatus for augmenting or facilitating flushing of impurities collected by a porous ferromagnetic matrix. The matrix is contained in a canister, through which an aqueous clay slurry is flowed as an applied field magnetizes the matrix to enable attraction of the discoloring magnetics. The periodic flushing of the matrix is rendered of increased efficacy, by applying auxiliary mechanical forces to dislodge the magnetics; or other disclosed means and methods may be used to facilitate the flushing operation.

I claim: 
     
       1. In a system for effecting the magnetic separation of magnetically attractable particles from a dispersion of such particles in a fluid carrier, said system being of the type including a non-magnetic cylindrical canister containing a ferromagnetic filamentations matrix therewithin and having inlet means at one end of said cylindrical canister and outlet means at the opposite end of said cylindrical canister; an electromagnetic coil surrounding said cylindrical canister for generating a magnetic field within said canister disposed in said field; means for flowing said dispersion axially through said matrix within said cylindrical canister from its inlet means to its outlet means and means for providing a flushing flow through said matrix to remove collected particles from the matrix to regenerate the same; the improvement comprising: a filamentation matrix having gradiations in density provided by successive zones of uniform density, wherein said zones are consecutively overlying cylinders, defining in total the cylindrical matrix, with each zone being more dense than its successor in the axial direction of fluid flow provided by the means for flowing the fluid through the canister from its inlet means to its outlet means for effecting the magnetic separation of magnetically attractable particles from said dispersion and with each zone being less dense than its successor in the axial direction of flushing flow provided by means for flowing a fluid from said outlet to said inlet means of said canister to remove collected particles from the matrix to regenerate the same.   
     
     
       2. In a system for effecting the magnetic separation of magnetically attractable particles from a dispersion of such particles in a fluid carrier, said system being of the type including a non-magnetic cylindrical canister containing a ferromagnetic filamentations matrix therewithin and having inlet means at one end of said cylindrical canister and outlet means at the opposite end of said cylindrical canister; an electromagnetic coil surrounding said cylindrical canister for generating a magnetic field within said canister disposed in said field; means for flowing said dispersion axially through said matrix within said cylindrical canister from its inlet means to its outlet means and means for providing a flushing flow through said matrix to remove collected particles from the matrix to regenerate the same; the improvement comprising: a filamentations matrix having gradations in strand diameter provided by successive zones of uniform strand diameter, wherein said zones are consecutively overlying cylinders, defining in total the cylindrical matrix, with each zone being composed of smaller diameter strands than its successor in the axial direction of fluid flow provided by the means for flowing the fluid through the canister from its inlet means to its outlet means for effecting the magnetic separation of magnetically attractable particles from said dispersion and with each zone being composed of larger diameter strands than its successor in the axial direction of flushing flow provided by means for flowing a fluid from said outlet to said inlet means of said canister to remove collected particles from the matrix to regenerate the same.   
     
     
       3. In a system for effecting the magnetic separation of magnetically attractable particles from a dispersion of such particles in a fluid carrier, said system being of the type including a non-magnetic cylindrical canister containing a ferromagnetic filamentations matrix therewithin and having inlet means at one end of said cylindrical canister and outlet means at the opposite end of said cylindrical canister; an electromagnetic coil surrounding said cylindrical canister for generating a magnetic field within said canister disposed in said field; means for flowing said dispersion axially through said matrix within said cylindrical canister from its inlet means to its outlet means and means for providing a flushing flow through said matrix to remove collected particles from the matrix to regenerate the same; the improvement comprising: a filamentations matrix having gradations in density and strand diameter provided by successive zones of uniform density and strand diameter, wherein said zones are consecutively overlying cylinders, defining in total the cylindrical matrix, with each zone being more dense and of smaller strand diameter than its successor in the axial direction of fluid flow provided by the means for flowing the fluid through the canister from its inlet means to its outlet means for effecting the magnetic separation of magnetically attractable particles from said dispersion and with each zone being less dense of larger diameter strands than its successor in the axial direction of flushing flow provided by means for flowing a fluid from said outlet to said inlet means of said canister to remove collected particles from the matrix to regenerate the same.   
     
     
       4. In a system for effecting the magnetic separation of magnetically attractable particles from a dispersion of such particles in a fluid carrier, said system being of the type including a non-magnetic cylindrical canister containing a ferromagnetic filamentations matrix therewithin and having inlet means to provide a feed flow from the outer annulus of said cylindrical canister radially inward to centrally located, axially disposed outlet means within said cylindrical canister; an electromagnetic coil surrounding said cylindrical canister for generating a magnetic field within said canister disposed in said field; means for flowing said dispersion radially through said matrix within said cylindrical canister from its inlet means to its outlet means and means for providing a flushing flow through said matrix to remove collected particles from the matrix to regenerate the same; the improvement comprising: a filamentations matrix having gradations in density provided by successive zones of uniform density, wherein said zones are successive annuli, defining in total the cylindrical matrix, with each zones being more dense than its successor in the radially inward direction of fluid flow provided by the means for flowing the fluid radially into the canister from its inlet means to its outlet means for effecting the magnetic separation of magnetically attractable particles from said dispersion and with each zone being less dense than its successor in the radial direction of flushing flow provided by means for radially flowing a fluid from said axially disposed, centrally located outlet to said inlet means disposed adjacent the outer annulus within said canister to remove collected particles from the matrix to regenerate the same.   
     
     
       5. In a system for effecting the magnetic separation of magnetically attractable particles from a dispersion of such particles in a fluid carrier, said system being of the type including a non-magnetic cylindrical canister containing a ferromagnetic filamentations matrix therewithin and having inlet means to provide a feed flow from the outer annulus of said cylindrical canister radially inward to centrally located, axially disposed outlet means within said cylindrical canister; an electromagnetic coil surrounding said cylindrical canister for generating a magnetic field within said canister disposed in said field; means for flowing said dispersion radially through said matrix within said cylindrical canister from its inlet to its outlet means and means for providing a flushing flow through said matrix to remove collected particles from the matrix to regenerate the same; the improvement comprising: a filamentations matrix having gradations in strand diameter provided by successive zones of uniform strand diameter, wherein said zones are successive annuli, defining in total the cylindrical matrix, with each zone being a smaller diameter than its successor in the radially inward direction of fluid flow provided by the means for flowing the fluid radially into the canister from its inlet means to its outlet means for effecting the magnetic separation of magnetically attractable particles from said dispersion and with each zone being composed of larger diameter strands than its successor in the radial direction of flushing flow provided by means for radially flowing a fluid from said axially disposed, centrally located outlet to said inlet means disposed adjacent the outer annulus within said canister to remove collected particles from the matrix to regenerate the same.   
     
     
       6. In a system for effecting the magnetic separation of magnetically attractable particles from a dispersion of such particles in a fluid carrier, said system being of the type including a non-magnetic cylindrical canister containing a ferromagnetic filamentations matrix therewithin and having inlet means to provide a feed flow from the outer annulus of said cylindrical canister raidally inward to centrally located, axially disposed outlet means within said cylindrical canister; an electromagnetic coil surrounding said cylindrical canister for generating a magnetic field within said canister disposed in said field; means for flowing said dispersion radially through said matrix within said cylindrical canister from its inlet means to its outlet means and means for providing a flushing flow through said matrix to remove collected particles from the matrix to regenerate the same; the improvement comprising: a filamentations matrix having gradations in density strand diameter provided by successive zones of uniform density and strand diameter, wherein said zones are successive annuli, defining in total the cylindrical matrix, with each zone being more dense and of smaller diameter than its successor in the radially inward direction of fluid flow provided by the means for flowing the fluid radially into the canister from its inlet means to its outlet means for effecting the magnetic separation of magnetically attractable particles from said dispersion and with each zone being less dense and composed of larger diameter strands than its successor in the radial direction of flushing flow provided by means for radially flowing a fluid from said axially disposed, centrally located outlet to said inlet means disposed adjacent the outer annulus within said canister to remove collected particles from the matrix to regenerate the same.